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Wednesday, July 26 2017 @ 08:42 pm EDT

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Why Pluto Had to GO!

Lunar & PlanetaryInternational Astronomical Union names 2003ub313 as "136199 Eris", or just ERIS for short. Read the announcement at PHYSORG.COM here.

Pluto HAD to be demoted from planethood, and here is my explanation why. What the International Astronomical Union, (IAU) did on August 24, 2006, was to assign the new desciption of "dwarf planet" to Pluto, but that falls short of truly describing what this object is. PLUS, if you think that what Pluto is called today will be what it's still called in another 2 to 3 years, well, I wouldn't try holding my breath expecting that to stay the same either.

There are several things that must be taken into consideration to have any success at an accurate description of what Pluto should be called. Here are my offerings on what I believe it MIGHT be called at some point in the not-to-distant future. It's only my own speculation, but let me present my case anyway.

A NASA artist's depiction of what Pluto and Charon may look like from the surface of one of Pluto's newest pair of smaller moons. Pluto is at right center, Charon to Pluto's right, one of the two new moons at the left of Pluto and the imagined appearance of the surface of the other new moon in the foreground.

Pluto was discovered by Clyde Tombaugh in 1930. Clyde was a Kansas farm boy who built his own reflector telescope and studied the planets by making carefully detailed pencil sketches of them. In 1928 he decided to send some of his drawings to Lowell Observatory in Flagstaff, AZ. He was both pleased and proud when he received a reply from Lowell saying they liked his pictures and he would be offered a job at Lowell if he could get to Flagstaff. I read somewhere that he left his farm home with less than a dollar in change in his pockets, bound by rail for northern Arizona.

Visual observations of Uranus and Neptune showed mathematical irregularities in their orbits in the late 19th century. The math hinted that something out beyond Neptune's orbit was the culprit. When Clyde arrived at Lowell Observatory, he was put straight to work on the problem of trying to find whatever may have been out there producing those minute little "tugs" on Neptune and Uranus. It would take him nearly 2 years to find it, but on February 18, 1930, he found his elusive quarry.

I was fortunate enough to have attended a presentation given by Clyde Tombaugh in 1988 at that year's Texas Star Party. Clyde was speaking on whether there might possibly be a 10th planet out there somewhere in the frozen outskirts of the solar system. Although in his 80's at the time, he was still a skilled an interesting speaker. Clyde began by telling everyone of his discovery of the 9th planet while using the 13" astrographic telescope at Lowell Observatory. This instrument didn't allow for visual observations, but instead it took images of the sky. Since planets move in their orbits around the Sun, any given image taken on any one night needed another image made of that same area a few nights later. Then the two images were set up in an instrument called a blink comparator which allowed the investigator to carefully examine the starfield with nothing more than his eyes to see if there were any "stars" that had moved from one night to the next. How time-consuming and tedious would you think such a job might be? And yet, this was how Clyde found Pluto.

But Tombaugh didn't stop there. The mathematical studies of the inconsistencies in Neptune's and Uranus's orbit had indicated that whatever was out there should be approximately 6 times the size of Earth. Pluto was MUCH to small to have been that suspect object, and so, for another 15 years, Clyde Tombaugh kept up his steady and monotonous search. Pretty much everyone felt there HAD to be something else out there, something considerably larger than Pluto's 1,300 mile diameter. Hearing Tombaugh give such a vivid, detailed description of "blinking" roughly 14,000,000 stars (by his own estimates), and then winding up his presentation by stating emphatically, "There is NO other planet beyond Pluto, no "Planet X", or I would have found it." That statement gave me all I needed to accept his word on the matter, but I really have to wonder what he would have said about the demotion of Pluto to "dwarf planet".

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Designing America's Return to the Moon - Part One

Lunar & PlanetaryThe designing of the spacecraft is underway that will someday soon return man to the moon. The actual construction won't be far behind. This new NASA program to return American astronauts to the moon and eventually to Mars is called CONSTELLATION, and I have to wonder whether this project will be any easier to complete than the Apollo Project of the last Century?
Apollo 17, last manned mission to the moon, sits in early morning bathed in floodlight and the gathering sunlight. When will we return to the moon?


Which young man or woman in today's high schools, or which college freshmen will be members of the first crew of astronauts to return to the Moon? It could just as easily be an Arkansas-led crew as to have a crew leader from any other state. I'm just biased towards the youth of our area. Who knows, but how wonderful that day will be when we finally return with the first lunar landings of the new millenium no matter where they may call home.

The knowledge that what we do this time around will be in preparation for an eventual permanent moon base, one designed for long-term lunar stays will make it all the more special. Much of what we leave behind on the surface with these next missions will in some way be utilized as permanent structures or storage facilities from where many truly far-ranging lunar exploratory excursions will depart.

NASA's Constellation Program will become the new "Apollo Program" of today, with the eventual long-term goal being nothing less than a manned mission to our sister planet, MARS!

The APOLLO Program - 1963-1972
An early NASA illustration of the Saturn I, the "mid-sized" Saturn V launch vehicles alongside the gigantic (proposed but not built) Nova rocket design which would have used 5 stages instead of the four used in the Saturn V.


President John F. Kennedy rallied the entire country to [achieve] the goal of landing a man on the moon, and [return] him safely to the Earth" in a speech to the joint house in 1963. And though Dubya is no "Jack" Kennedy by a long, LONG shot, he did lay out the goal for America to return to the Moon and establish a permanent moon base as a precursor to an eventual manned trip to Mars sometime in the future. So far, engineers are only working on the new designs for both a new heavy-lift rocket and a new crew rocket. I can liken it to how the Apollo program grew and evolved from what was first envisioned to what we finally had later when we actually began our first exploration of the moon between 1969 and 1972.

Early in the "Race to the Moon" when America and Russia were competing to see who could put a man on the moon ahead of the other, there was no definitive design for what our first moon rocket would look like. About the only thing most engineers could say for sure was that it would take an enormous vehicle to achieve the launch to orbit of whatever we'd be sending on out beyond Earth to the moon. Whatever it was to be would have to achieve a speed of at least 25,000 mph while pushing dozens of tons in the right direction. Not even the design of the flight plan was in place when we saw one of our first concept pictures such as the image above.

Some engineers wanted to build a gigantic single-stage behemoth that would go directly from Earth to the moon as a single unit. The laws of physics demanded that that idea be scraped in favor of smaller multi-stage vehicles. Weight was going to be the deciding factor in how we got to the moon, if indeed, we could even get there at all.
The evolution of designs for the Lunar Module for the Apollo program. What was first designed was not especially similar to what the final version looked like. Weight decided nearly all of the design changes seen in this image.
The flight plan that was finally settled upon was for a very large rocket with four stages that would place in orbit the crew module and another craft designed ONLY for landing on the moon, a "Lunar Module". These two components would be shot away from Earth by the third stage at the required speed of 25,000 mph in order to escape the gravitational pull of Earth, and allow the two primary components to reach and finally orbit the moon.

The crew module, called the Command Module, would sustain a single astronaut in orbit around the moon while the other two of a three-man-crew would enter the Lunar Module for the trip down to the surface of the moon. All the consumables for the trip would be contained in what was called the Service Module which would remain mated to the Command Module until just before re-entry into the atmosphere by the Command Module and the crew.

This flight plan was referred to as Lunar Orbit Rendezvous due to the Command and Lunar Modules being required to dock, undock and descend, and later return to orbit to once again dock, and allow for the three man crew to return safely to the Earth in the Command/Service Module leaving the now useless Lunar Module behind. In the HBO series "From the Earth to the Moon", the fifth episode called "Spider" deals specifically with all that went into the Luner Orbit Rendezvous mission and the extremely difficult problems involved with the creation of the Lunar Modules by the Grumman Corporation. Enormous difficulties were encountered, and overcome, and this is my personal favorite episode of this outstanding and important series.

Click read more for the rest of Part One including images of our new rocket designs.
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When This Comet Dies

Lunar & PlanetaryUPDATES CONTINUE:

#5 Number of fragments listed reaches 71 as of 06/01/06! Click to view ALL orbital elements

#4 The latest incredible new image of Comet 73P/Schwassmann-Wachmann 3 from the orbiting Hubble Space Telescope on APOD for May 3rd.

#3 Click on the link to APOD for April 26 for an outstanding image of fragment "B" of comet S-W 3 taken by the 8.2 meter Kueyen instrument of the Very Large Telescope of the European Southern Observatory. Numerous pieces can be seen in that image indicating that this comet is still crumbling right before our eyes. S-W 3 passes nearest to the Earth on May 13, and nearest the Sun on June 6-7.....ALSO.... click "read more" below for Mike Holloway's latest image at the end of this article. This image is being carried on"Cometography" website.

#2 It seems that a possible break-up of the nucleus of fragment "B" may be underway over the last few days. In a negative image made by Dr. P. Clay Sherrod of Arkansas Sky Observatories, which was reprocessed by Mike Holloway, a suspicious brightening behind and separate from the nucleus can be seen. (click "read more")

#1 As of April 11, 2006, the number of individual fragments which have been located and associated with S-W 3 has reached 40 fragments according to a web article in Sky & Telescope !

Every so often, astronomy offers all of us who appreciate the beauty of the universe some little surprise. Both amateur and professional astronomers alike have recently been monitoring a well-known short-period comet that has begun to disintegrate and is soon doomed to fade out of existence. In the next 3 to 4 months, Comet 73P/Schwassmann-Wachmann 3 will be front-and-center on the astronomical stage.


As it sings its swan song, every person on the planet will have a chance to see Comet 73P/Schwassmann-Wachmann 3 (I'll just shorten it to S-W 3) as a classic "iconic" comet... with the fuzzy head and a nearly stellar nucleus, and with a faint and likely short to medium length tail which will always be pointing away from the Sun. S-W 3 joins a few other recent comets that have broken up into fragments while the world watched in the last 150 years or so.

Fragment "C" of Comet 73P/Schwassmann-Wachmann 3 by Mike Holloway. This is a cropped image of a 3-frame mosaic of fragments C, B, and E, which may be seen by clicking on the link to Holloway Comet Observatory to the right.
The most spectacular of these recent fragmented comets was Shoemaker-Levy 9 which slammed its 22 tiny comets into Jupiter in 1994. (See image below) I can clearly remember setting up my telescope on July 16, 1994 and bringing Jupiter to a sharp focus at low power. There before my eyes was a huge smudge of brownish-black, larger than the Earth, where a fragment had crashed into the upper layers of the giant planet's outer atmosphere.

AOAS's resident comet specialist and astrophotographer, Mike Holloway, has been keeping a watch on S-W 3 for some time now. We can all follow his photographic journal of what transpires with this comet on his website by clicking on Holloway Comet Observatory. While on Mike's site, rummage through his extensive collection of comet images from the past few years, as well. Although he hasn't been doing this for a long period of time, Mike works very closely with Arkansas' top astronomer, Dr. P. Clay Sherrod, better known around the world as Dr. Clay. There are some remarkable images from Mike's rapidly growing portfolio.
Called by many a "String of Pearls", Comet Shoemaker-Levy 9 fragmented into at least 22 pieces that each crashed into Jupiter in the summer of 1994. Hubble Space Telescope image.
We at AOAS are all proud of Mike and his dedication to comet astrophotography and we're even more proud that he's a dedicated member of our club. As the years go by, I see him becoming someone known around the world as a well-known and noteworthy comet photographer, someone professionals turn to for the images that might make the difference in determining essential information about these wandering vagabonds of our Solar System.

Click read more for the rest of the story.
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Speculations on the Comet's Last Stand

Lunar & PlanetaryComet 73P/Schwassmann-Wachmann 3 (S-W 3) has all but disappeared after it's most recent passage through the inner solar system. It's fair to say that this was its final such trip. All that will remain for the immediate future is for the rocky, silicate materials that had been bound up inside it to slowly dissipate and spread out. It may be possible for some of this material to burn out in Earth's outer atmosphere as little meteors in their final blazes of glory.
Comet S-W 3 and the Ring Nebula on May 8th. Photo courtesy Mike Holloway, Holloway Comet Observatory, Van Buren, AR.

Not being someone who is especially enamored with comets, it may have passed by Earth this time without my ever having thought twice about it. But comet 73P/Schwassmann-Wachmann 3 made me take notice this time, made me wonder a little more than usual about comets in general, and about this particular one more than most others.

Professional astronomers were expecting it to pass through the inner sanctum of the solar system in late 1995 as an uninspiring object barely even visible to all but the largest amateur telescopes. Yet, in October of 1995, S-W 3 was recovered and at first mistaken for a new comet due to it appearing several hundred times brighter than had been expected. Why was that?

The answer became obvious when professional observatories imaged the comet and discovered that it had split into at least four pieces. When events such as this occur, there is usually a large amount of deeply buried pristine material suddenly released to reflect more sunlight and make these objects brighter than expected. The frozen gasses sublimate into a bigger coma than normal, and any solid particles of rock and metal are freed to reflect even more sunlight and lend their own contribution to the overall effect.

Once I had started reading the magazine articles about this comet's return, and after Mike Holloway had sent me some images he'd taken earlier this year, I began to get interested in what might happen this time. After the successful NASA mission to smash a projectile into comet 9P/ Temple 1 on the Deep Impact mission last year, I saw the images of that comet's exterior and was surprised by how smooth and "solid" looking it was. Of course, Temple was a much bigger comet than S-W 3 to begin with.

Fragment B of comet S-W 3. A composite of 8 X 8 sec exposures by Arkansas Sky Observatories and Dr. P. Clay Sherrod taken on May 19, 2006. Note in the inset image the small trailing fragment which had just been released and is beginning to drift away from the larger piece.
But as I kept reading about S-W 3's approach and realized that it was continuing to break up into even more fragments, I imagined that its appearance may have have been something more similar to that of asteroid Itokawa, the "rubble-pile" of rocks and dust that the Japanese asteroid sample return mission had revealed to us early this year.

No one knows why S-W 3 is breaking up as much as it is, but I had to wonder whether or not it had ever have been a very compacted or compressed object to begin with. Maybe it was simply a loose conglomerate of numerous small pieces barely held together by weak gravity to begin with. Or, maybe it had met up with a small asteroid sometime in its past and that impact could have caused numerous fractures throughout its mass. The slight gravitational influence of the Sun or some other planet may have been all that was needed to cause the fragmentation effect and help make it ready to crumble away during this particular trip inwards toward the Sun.

Whatever the reason, S-W 3 is basically dissolving right before our eyes, providing astronomers with a rare opportunity to see how such processes work. We need to study how asteroids and comets are held together in order to eventually use our technology to deflect one sometime in the future. The last thing the human race wants to see is a Shoemaker-Levy 9 type object breaking up and striking Earth with one or more catastrophic impacts. Earth's very existence may depend on such knowledge.

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Stardust Comet Particles Tell Tales of Fire and Ice

Lunar & PlanetaryThe wonderfully successful Stardust mission to retrieve cometary and interstellar dust grains is now beginning to reveal to scientists the secrets it was sent to find. It re-entered Earth's atmosphere at a near-record speed of almost 30,000 mph on January 15, 2006, with the pristine dust particles of comet Wild 2 (pronounced 'Vilt 2') as well as other particles gathered from between the planets on its way to the comet safely packed away deep inside.

Once it had landed at the Dugway Proving Grounds in Utah, it was recovered, transported to a special lab at a NASA facility in Houston, and research is now underway on the first of these exciting never-before-seen-particles.
Brilliantly illuminating the countryside over the Pacific Northwest and Northern Nevada and Utah, Stardust announces its return to Earth after a spectacularly successful cometary material return mission.


Early reports from Stardust mission scientists reveals that there are materials found within the dust grains gathered from Comet Wild 2 that had to have formed in very high-temperature conditions, namely, the mineral olivine. This was totally unexpected as Stardust Principal Investigator Donald Brownlee of University of Washington at Seatlle explains."The interesting thing is we are finding these high-temperature minerals in materials from the coldest place in the solar system." Most AOAS club members will remember some of the meteorites that I've brought to club meetings from time-to-time, and olivine is a common ingredient in meteorites and in many Earth minerals. Another well-known name in meteoritical research is Michael Zolinsky who happens to be the curator and a co-investigator on the Stardust team says, "[finding] high-temperature minerals...supports a particular model where strong bipolar jets coming out of the early sun propelled material formed near to the sun outward to the outer reaches of the solar system."

Tiny fragment of the high-temperature mineral olivine found as one of the comet dust grains imbedded within the aerogel material on the Stardust mission.
Olivine is one of the most common minerals in the universe. It's the primary ingredient in the green beach sands found on some Hawaiian beaches, and they are, of course, formed from volcanoes. Quite surprising to find such a mineral within cometary dust.

While olivine is a component of iron and magnesium, as well as other elements, the olivine in the dust taken from the Wild 2 samples is also rich in calcium, aluminum, and titanium.

The remarkable material which performed the task of capturing these dust grains and interstellar particles is called Aerogel, and is about 1000 times less dense than glass. To look at it, one can easily see where it gets the nickname "solid blue smoke".

Click "read more" for an image of Aerogel, more images of cometary particles, and links to websites to learn more about Stardust
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Hayabusa - The Japanese Asteroid Sample Return Mission

Lunar & PlanetaryUPDATE: Japan's "Falcon" Wounded! Mission in Jeopardy!

Hayabusa (Japanese for Falcon) has encountered serious problems and the mission is in jeopardy. For an explanation of what the situation currently is, the Planetary Society article HERE is available for review.

A little known mission to return a sample of an asteroid to scientists on Earth has been underway for the past few years. Launched on May 9, 2003, the spacecraft's name is Hayabusa, and its mission is to rendezvous with asteroid Itokawa,

"Rubble-pile" Earth-Crossing Asteroid Itokawa.
land a very small robot craft named Minerva on its surface, scoop up a sample of asteroidal material, bring that back to Hayabusa, and eventually return it to Earth. Until the last two weeks, everything had gone pretty much as planned, but trouble now threatens to push back the return date for when the sample will be returned to Earth.

Asteroid Ida and its tiny moon Dactyl from the Galileo spacecraft's flyby in the early 1990's.
The Japan Aerospace Exploration Agency's (JAXA) Institute of Space and Astronautical Science (ISAS) spacecraft "Hayabusa" was launched on May 9, 2003 and arrived at its destination on September 12, 2005. Asteroid Itokawa has turned out to be what's known as a rubble-pile asteroid, an amalgam of rocks, rubble and dust held together by its miniscule mutual gravitational attraction. It just "looks" so much different from the other asteroids that we have images of, such as asteroid Ida below, instead of a large object with a solid looking surface spotted with anywhere from several dozen to several thousands of impact craters from other objects striking it. Itokawa is as rough as a cob with only a few spots of smooth surface area.

The smooth area seen in the image above is where the tiny (1 lb.) Minerva lander touched down for a sample of the asteroid's material for return to Earth.

While Hayabusa has been parked in orbit near Itokawa since September 12, the spacecraft has been experiencing some troubles in the past few weeks. Scientists all but lost contact with the craft 3 weeks ago, but are slowly regaining communications. The craft made its way to Itokawa by way of a newly developed Ion engine, and if the re-establishment of all communications and functions continues, the Ion engine will soon be re-ignited to allow Hayabusa to begin its return voyage to Earth. JAXA's website has all the latest information by clicking the Hayabusa info column here.

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Stardust Spacecraft to Return January 15, 2006

Lunar & PlanetaryOn the evening of January 15, 2006, at about 4:00 am Arkansas time, a brilliant fireball will begin its passage over the Pacific NW on its way towards a landing in Utah. For people all over that area of the United States, the fireball will be a rare and wonderful site for about a minute. But for NASA scientists working on the Stardust mission, it will be "Welcome home, stranger" as the spacecraft's return module hits Earth's atmosphere at a higher speed than any other manmade object in history. It will be an anxious time until the little 100 lb. object slows itself enough to first release the drogue, and then the main parachutes, that will allow it to land unharmed in the Dugway Proving Grounds in the Utah desert.

UPDATE: January 15, 2006......SUCCESS!! STARDUST HAS RETURNED SAFELY AND EXACTLY AS PLANNED IN THE PREDAWN HOURS OF SUNDAY MORNING.

UPDATE: Jan 1, 2006
Amateurs are asked to participate in watching, and recording, the re-entry of the Stardust return canister as it lights up the Pacific NorthWest. This following info comes from Night Sky Network.

Stardust Reentry Observing Opportunity and Call for Amateur Astronomer Participation

Stardust is the first U.S. space mission dedicated solely to the exploration of a comet, and the first robotic mission designed to return extraterrestrial material from outside the orbit of the Moon. Additionally, the Stardust spacecraft will bring back samples of interstellar dust, including recently discovered dust streaming into our Solar System from the direction of Sagittarius. Stardust is on its way back home, due to arrive as a visible "meteor" on January 15 starting at around 2 am PDT (3 am MDT). The "meteor" will be visible from several Western states, and especially good in Nevada and Utah. The capsule will actually make landfall in Utah, southwest of Salt Lake. The peak optical brightness is anticipated at minus 7.8. It will be hard to miss if you're in the right place.

Amateur astronomers are invited to participate in the mission! If you are interested in participating, the team is looking for video, still and even visual observation reports. If you are interested there is an observation form and list of observers here: http://reentry.arc.nasa.gov/registrationobserver.html
To learn more about participating in this event, go to the press release at: http://stardust.jpl.nasa.gov/science/feature002.html

The Stardust spacecraft is almost home now after a nearly 3 billion mile journey. Onboard are pristine samples of interstellar dust grains, and the first ever samples of particles returned from a comet.
NASA's Stardust spacecraft will have traveled some 2.89 billion miles by the time it returns its precious cargo to Earth on January 15, 2006. It successfully encountered periodic Comet 81P/Wild 2 (pronounced 'Vilt 2') in early January of 2004, when it opened its collector grid to allow microscopic particles of cometary dust to be captured in a special material known as Aerogel. This material is 99.8 percent air, and is some of the most highly efficient insulating material ever produced. Insulation is not its intended use, though, because it does an exceedingly good job at safely capturing and holding tiny particles only a few microns across which can impact at speeds of 10,000 mph or more.

Periodic Comet 81/P Wild 2
Stardust was the fourth of NASA's revolutionary missions designed to be cheaper, faster, better. The prime focus of the mission was to capture and return material from a comet, but it also used its unique aerogel material to capture unaltered interstellar dust grains from two different areas of its orbital path through the solar system. Scientists will be interested in finally knowing how unaltered interstellar dust grains compare to the micrometeorite particles that are collected regularly. These tiny objects, only a few microns in diameter, have experienced heating as they hit our atmosphere and are rapidly decelerated enough to eventually float down through the upper atmosphere to the ground.

But it is the cometary material that is of prime interest to NASA scientists, and especially to Dr. Donald Brownlee, principal investigator of the Stardust mission. Brownlee regularly studies the micrometeorites that are scooped up by ultra high-flying U-2 aircraft. These are part of the normal "daily delivery" of meteoritic material that enters the earth's atmosphere and gently rains down across the entire surface of the Earth. Believe it or not, we have all eaten meteoritic materials in the crops which are grown in the farm lands around the world. This material is in cabbage and lettuce and all other crops with large leaves, where the material falls onto the leaves and is then washed down by raindrops into the space between the leaves which is where it can be found when we eat the crop. Umm, tasty!

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Spirit and Opportunity Mark One Martian Year

Lunar & PlanetarySpirit and Opportunity, NASA's twin Martian Rovers, are marking their 1-year anniversaries on Mars. But one year on Mars equals nearly 2 Earth years. Both these hearty robots have now exceeded their originally intended 90-sol "warranty" periods by more than 7 times, and yet, both are still going strong!
Talk about SUCCESS! The twin Martian Rovers just may outlive a certain popular rabbit! They just keep going, and going, and going....


NASA's Mars Exploration Rovers are the longest lived planetary surface explorers in history, and they don't appear to be any worse for wear after now completing their first full Martian year on the fourth planet from the Sun. One year on Mars is equal to 687 Earth-days, and since a "day" on Mars (called a 'sol') is 24hr and 40min long, a full year on Mars itself is actually 669 Martian days long. How remarkable their stories are, and how fascinating the photojournals of their travels have been. The total number of pictures returned to Earth from both MER rovers to date are: Opportunity - 61,567 raw images....and Spirit - 71,778 raw images. For anyone who would like to view ALL their images, they can be found by clicking on this link: mars rovers gallery

Or perhaps you'd be more interested in viewing NASA's own slide show of the pair's journey since they landed in January of 2004. This slide show will be slow to view on dial-up modems, but DSL or cable subscribers to the internet will be quite pleased at this amazing set of images and their educational captions. See all that this great site has to offer for yourself at the Mars Exploration Rover homepage. Once there, look for and click on the link for the slide show.

Click READ MORE for maps of the terrain crossed by the MER's, and for the rest of this story.
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Congratulations, It’s Twins!

Lunar & PlanetaryThe European Southern Observatory Very Large Telescope has discovered an asteroid with TWO orbiting moonlets, a first for any known asteroid. The Yepun instrument of the VLT facility made the historic find by utilizing the adaptive optics system instrument known as NACO. Results were published in the August 11 issue of the Journal Nature.

Discovered in 1866, asteroid 87 Sylvia, named for the mythological mother of the founders of Rome, now reveals her twin sons, Romulus and Remus.
As though they were technicians conducting an ultrasound examination of a fetus, a surprise awaited observers using the 8.2 meter Yepun telescope at the European Southern Observatory in Cerro Paranal, Chile. A team led by Franck Marchis of University of California Berkeley and co-discoverers Pascal Descamps, Daniel Hestroffer, and Jerome Berthier of the Observatoire de Paris, France, had been using the telescope to observe asteroid 87 Sylvia to check for moonlets circling about the main asteroid. Measurements had previously indicated that 87 Sylvia was an asteroid with one small companion in 2001 after work done by Mike Brown and Jean-Luc Margot at the Keck telescope in Hawaii.

Marchis and colleagues made 27 observations with the huge 8.2 meter Yepun telescope during a two-month period. On every image the known companion moonlet was seen allowing for that object's precise orbital elements to be determined, but 12 of those images revealed a separate, smaller companion orbiting closer in towards the main asteroid. What was once a single moonlet, is now twins.

The 87th asteroid discovery, 87 Sylvia has been determined to be a huge pile of rubble loosely joined together by a compilation of debris giving the overall appearance of a potato shaped asteroid. It would seem that at some time in Sylvia’s ancient past, something struck her with enough force to completely shatter her into a pile of debris, of which the attendant moonlets may simply be left-over material that didn't rejoin the main mass. This asteroid has a density estimated to be only 20% that of liquid water, and could be up to 60% empty space.
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Mars or Bust - Mars Reconnaissance Orbiter

Lunar & Planetary
An Atlas V rocket blasts off from Cape Canaveral Air Station at approximately 7:43 a.m. on August 12, 2005. Its payload is the Mars Reconnaissance Orbiter, and by November 2006, it will begin the most highly-detailed, in-depth study of Mars yet conceived.
Rising into the air in the morning sun, an Atlas V rocket lifts off for the Red Planet. In the nose cone, the largest spacecraft ever sent to Mars huddles under the shroud, wings folded, antennae tucked tightly away. It will arrive in March 2006, seven months from now, and then spend another six months gradually circularizing its orbit until its 25-month science mission can begin. That mission is a prestigious one, but it will continue to serve future missions to Mars by using its sophisticated high-speed communications system to relay data back-and-forth at more than 10 times the rate of any other communications system to date. Say hello to the fast-talking new kid in orbit, the Mars Reconnaissance Orbiter, or MRO.

It needed a heavy-lift rocket to get off the Earth and send it some 70 million miles towards the planet Mars. As the hours passed on launch day, big grins pervaded the control room as item after item on the checklist were crossed-off satisfactorily. So far, so good. MRO is now in the "cruise" phase of its mission.

It's dimensions are impressive standing 21 feet tall with a 10 foot-diameter communications antenna.
Aerobraking will take MRO skimming just above the thickest part of Mars' atmosphere numerous times, each pass slowly refining the shape and altitude of its orbit until it becomes nearly circularized by September 2006.
When its solar panels are fully extended they will be 45 feet wide from tip-to-tip. The entire craft weighs a little over 4,800 lbs, and nearly half of that weight at launch will be the fuel needed for use in the 20 on-board thrusters that will control it while in orbit. MRO was built by Lockheed Martin Space Systems in Denver, CO.

This mission to Mars will seek to establish the following goals. 1) Characterize the present climate of Mars. How exactly does the climate change from season-to-season and from year-to-year. 2) Characterize Mars atmosphere and monitor its weather. 3) Investigate complex terrain on Mars and identify water-related landforms. 4) Search for sites showing stratigraphic or compositional evidence of water or hydrothermal activity. 5) Probe beneath the surface for evidence of subsurface layering, water and ice, and profile the internal structure of the polar ice caps. 6) Identify and characterize sites with the highest potential for future landings on the surface to include sites from where sample return missions might land. 7) Relay scientific information to Earth from current and future Mars surface missions.

Click "read more" for the rest of this story.

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Become a card-carrying member of AOAS. Paying dues gives you several advantages over other registered users, including a subscription to the club newsletter, an AOAS.ORG e-mail address, use of club materials, including books and telescopes, and access to the Coleman Observatory facilities. On top of all that, you also qualify for a 20% discount on all books at any Books-A-Million location.

To get your membership application, click here.